The wage of hiring a diver may take hundreds or even up to thousand U.S. dollars per hour, and by using the propelling device of this invention, any person (if his/her physical condition allows) can embrace the device and do the work.
The unique feature of this case is to design a propelling device mainly made from EVA (ethylene vinyl acetate) and is bound with chest and to be in unity with the user, thus without rudder the user can swim in any style and have two hands free either during swimming or submerging, particularly when submerging, so that the user can do some work, for instance checking the surface situation of a ship hull or the propeller of a merchant ship, cleaning or even achieve under-water welding work. The invention has been tested numerously, particularly for submerging, and is proved reliable, excellent and successfully.
The invention is ready to be exported to U.S.A. with a cheap and reasonable price, so that every sea lover can enjoy swimming and submerging. Particularly, it is a gospel for a merchant ship owner, who usually is reluctant of cleaning ship hull for its high expanse. Now many sailors can be distributed with this invention to clean the hull to save tremendous energy consumption due to friction of ship hull with water.
Some prior arts have been granted patents in USA, such as
1.U.S. Pat. No. 5,105,753 of "Multi-purpose underwater propelling device" by Chih et al. PA1 2. U.S. Pat. No. 4,811,682 of "Mini inflatable yacht" by Hwang et al. PA1 3. U.S. Pat. No. 2,722,021 of "Surface and sub-surface human being propulsion device" by W. C. Keogh-Dwyer. PA1 4. U.S. Pat. No. 4,840,592 of "Power driven underwater viewing platform" by A. B. Anderson. PA1 5. U.S. Pat. No. 3,536,025 of "Motorized surfboard" by Tireney. PA1 6. U.S. Pat. No. 3,442,240 of "Power swimming aid" by F. J. Wild et al.
Except the one of Keogh-Dwyer, none of abovesaid prior art can achieve the abovesaid object, like under water welding, which requires a firm hand to weld the ship accurately.
Besides, since no rudder is needed, the structure is the simplest compared with all the Granted patents (except "Sailboard with removable floats" by Chinnery) and the propelling direction can be easily controlled by turning his own body.
Though Chih et al. of U.S. Pat. No. 5105753 discloses a swimming propelling device (FIGS. 3, 4-1) with a floating body 10, a battery 24, a motor 22, switch 55, and a re-charging outlet 132, the abovesaid unique features of (1). Let two hands free in order to work; (2) omissions of the rudder are not found in the prior arts of Chih.
Though Keogh is the only reference which has similar objects as this case, the structure of Keogh is much more complicated. Accordingly, the cost will surely be much more expansive than this case. Besides, a gas release valve, a water entry and escape valve, a gas pressure chamber, means connecting said gas pressure chamber, a control valve . . . are provided in the said Keogh, the more complicated the structure is, the more problems will occur. The cost of the Keogh is unknown; however, since its structure and working principle correspond to a submarine, the applicant estimates the cost ratio between two inventions can be roughly estimated as the one between a submarine and a simple powered canoe. Thus the invention can be manufactured in a much cheaper price.
Concerning the flexible and waist strap, there is still difference therebetween, the strap of this invention utilizes push button type, so that in case of emergence, a user can instantly give up the propelling device by just pushing the button. However, if the examiner insists that the design thereof is obvious, the applicant is willing to remove this strap from the protected scope.
The combination of Chih et al. and Keogh-Dwyyer falls short of applicant's invention because it could not be used under water to let two hands free.
Hwang of U.S. Pat. No. 4811682 discloses a swimming propelling device including a flange and a float 23. Not disclosed by Hwang is a float in the form of a foam plate, a connecting slot, and an on/off switch.
The flanges of this invention are provided along the two sides of the floating body, which can also have the function of stabilization when being used under water, however the flange of Hwang is provided along the inner side of inflatable bladder which can not be used underwater and merely for engagement. Similarly the float member 28 of Keogh-Dwyer could not be used along.
Though this invention can be utilized for swimming, it is particularly useful for submerging work. However, the function and object of the invention "Power driven underwater viewing platform" by Anderson is different from this invention, same for the inventions of Tierney, Bonafous and Wild et al.